Chevelle Restoration and Authenticity Guide 1970-1972. Dale McIntosh
target="_blank" rel="nofollow" href="#fb3_img_img_66da454b-4eb6-5fb7-b1cd-9d7ef0dc3b55.jpg" alt="Image"/>
Make note of how your fuel lines run and take special note of the area around the passenger-side rear coil-spring tower. This area can get interesting when installing the new lines. Photo documentation of how the originals were routed will aid in your installation of the new ones.
Remove the fuel lines by lifting them up and over the axle crossmember and pulling them back out through the frame, where they run along and inside the front passenger frame horn. Take note of where they run in the frame and out of the front crossmember as this will help you understand where they need to run come reinstallation time. You will find it easier to remove them one at a time, but both can be done at one time. Try to not damage or bend these as you are removing them; you may want to use them to compare to the new lines to ensure you not only have the correct replacement lines but also that the new ones are bent accurately. Once these are removed safely, drain them and set them out of the way.
The fuel-line clips are different depending on if used on a single line or dual line, so document what type you have, the color of each clip, and the placement and bolt-head design of each. Also note if the coiled sleeve is on the line in the area of the clip or not as this too will make a difference on which size clip was used.
Loosen and remove all the brake lines at the distribution block while it is still bolted to the frame. Depending on its condition, heat may be required for this step. Use precautionary methods when handling a torch and hot brake fluid, as severe injuries may occur if hot brake fluid spills on you.
Brake Hard Lines
Moving on to the driver’s side of the frame, start by photographing the placement and shape of the brake lines on the frame. Your original photos can be used later as a reference if you are having trouble with the replacement lines and how they are bent.
Now that you have that done, begin by removing the brake lines at the front. You already removed the flex lines running from the drums or rotors to the front frame brackets during the front disassembly process, so go directly to the hard lines. Separate the crossover line on the front crossmember and the short line running from the distribution valve mounted on the frame on the driver’s front to the left front brake. Remove the clips from the crossover line again, noting their original color. If the two lines running from the distribution valve up the master cylinder have not yet been removed, go ahead and do so at this time. As before, heat may be required to get these to break loose, so use the same precautions as you did before.
Pay attention to each clamp and bolt when removing. You may find several different sizes, colors, and styles of clamps. It is important to document these and replace them in the original location during the restoration. Also make note of the head markings and type of bolt.
Pay attention to this bracket; there can be two different styles used on these cars. Usually there is one open flat bracket and one looped closed bracket. There does not seem to be any rhyme or reason as to which type was used or when. The fuel line uses a similar bracket, so don’t get them confused.
Moving rearward, disconnect the main line from the rear of the distribution valve. Chevelles used at least two different designs for the distribution valves: one being cast iron and the other is brass. Remove the valve from the frame and put it and its bolt in a separate bag. Note which valve you have because they will be restored differently.
Remove the main brake line from the frame while again noting the different-size brake line clamps, location, color, and different bolt markings and type. Clamps are different depending on the diameter of the line at that particular location, including the dimension of the protective spring sleeve, and will also be color coded. These coil sleeves are installed to protect vulnerable areas of the brake line from road debris, such as rocks, as well as protecting some of the main bends from kinking or crushing. Tag the clamps while again noting their location and bolt usage and put them into a bag.
On disc-brake cars, another valve was used at the driver-side rear crossmember just in front of the driver-side rear wheel. This valve is called the brake hold-off valve, and it is only found on cars with disc brakes. If it is not there, it is because you have four-wheel drum brakes or someone incorrectly replaced brake lines and left it out. Lack of use of this valve on disc-brake cars will cause the car to nose dive during braking.
The hold-off valve is found on the driver-side rear crossmember. Loosen the lines to and from the valve and use heat if needed to separate them. In rare cases, these valves will need to be replaced or rebuilt. Both rebuild kits and replacement valves are available aftermarket. Place it in your bag with your other brake line pieces.
As in other areas, heat may be required to loosen the lines. Since you already removed the rear flex hose at the time you dropped the differential from the frame, your brake line removal is now complete. It is a good idea to put the flex line and bracket in your bag tagged for brake line hardware.
Restoration and Assembly of the Frame
Congratulations! This marks the completion of your frame disassembly and the beginning of the restoration of the frame and all associated bolt-on hardware items. Here is where the excitement begins and you will start to see the fruits of your labor.
For ease of understanding, let’s restore the frame and chassis in the same order you disassembled it. It was touched on earlier, but the very first thing you will want to do is examine the frame and determine if it is the right candidate for restoration. If it has any major issues, such as rust holes, bends, or cracks, it may be a good time to locate a good donor frame to use for your project. Frames for Chevelles vary slightly between years, and there are also differences between the bodystyles (coupe, wagon, convertible, El Camino, two-door versus four-door), so make sure you are replacing it with the right donor. In most cases, you can also use a frame from another GM A-Body car.
Doing your homework, taking your time, and using quality products will give you the end result that will make you feel great about the time and money you put into your project.
Frame Cleaning
It is best to take your frame and sandblast it or use other means of media removal, such as aluminum oxide, walnut shells, or plastic media. Sand and aluminum oxide are usually fairly inexpensive, not very time consuming, and allow you to start with fresh bare metal as well as remove rust, unlike some forms of media blasting that will not remove rust. There are other means of paint removal, but most of them are very time consuming or expensive.
You might also want to consider hiring a company that will do on-site blasting with their equipment, though your local surroundings will dictate if this will work or not. There are several varieties of these services as well, including high-pressure water, walnut, glass, plastic media, etc. If you are not close to a blasting facility, you can purchase a do-it-yourself compact blaster for little money; although, a fairly high-volume, high standard cubic feet per minute (SCFM) air compressor would be necessary. If you are using silica sand, you must also use a fresh-air hood and blast upwind of your project.
For the best bang for your buck—and regardless if you are doing the work or farming it out—you are better off if you put most of the parts that need blasting aside and wait to do them all at one time. It is not suggested to sandblast any large sheet metal items, however, as warpage